With the development of the digital city,data and data analysis have become more and more important.The database is the foundation of data analysis.In this paper,the software system of the urban land planning database...With the development of the digital city,data and data analysis have become more and more important.The database is the foundation of data analysis.In this paper,the software system of the urban land planning database of Shanghai in China is developed based on MySQL.The conceptual model of the urban land planning database is proposed,and the entities,attributes and connections of this model are discussed.Then the E-R conceptual model is transformed into a logical structure,which is supported by the relational databasemanagement system(DBMS).Based on the conceptual and logical structures,by using Spring Boot as the back-end framework and using MySQL and Java API as the development tools,a platformwith datamanagement,information sharing,map assistance and other functions is established.The functionalmodules in this platformare designed.The results of J Meter test show that the DBMS can add,store and retrieve information data stably,and it has the advantages of fast response and low error rate.The software system of the urban land planning database developed in this paper can improve the efficiency of storing and managing land data,eliminating redundant data and sharing data.展开更多
This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River water- shed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GI...This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River water- shed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) technology. Then, using the famous land-use change model of Conversion of Land Use and its Effects at Small re- gional extent (CLUE-S), this paper simulated the land use changes under historical trend (HT), urban planning (UP) and ecological protection (EP) scenarios considering urban planning and ecological protection over the next 20 years. The simulated results under UP scenario in 2020 were compared with the planning map to assess the feasibility of us- ing land-use change model to guide regional planning. Results show that forest land, dry farmland, paddy, and shrub land were the main land-use categories. Paddy and dry farmland being converted to urban area and rural settlement characterized the land-use change from 1988 to 2004. The main land-use categories changed over time. Landscape-pattem fragmentation will be worse under HT and UP scenarios, but better in EP scenario. The comparing results of simulated map with planning map in 2020 show that land-use change model is powerful tool to guide regional planning. Land-use scenarios can support regional planning and policy-making through analyzing future consequences scientifically.展开更多
The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-m...The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.展开更多
This paper explores the potential application of a modified version of the Non-dominated Sorting Genetic Algorithm (NSGA)-II for land-use planning in Mediterranean islands that constitute a geographical entity with si...This paper explores the potential application of a modified version of the Non-dominated Sorting Genetic Algorithm (NSGA)-II for land-use planning in Mediterranean islands that constitute a geographical entity with similar characteristics. Study area is the island of Naxos, which is a typical Mediterranean island. In order to monitor the land-use changes of the island for the period 1987-2010, object-based classification of three Landsat images has been carried out. The 1987 land-use classification defined the initial population for the Genetic Algorithm (GA) and the aim was to provide the optimal development scenario for Naxos island taking into consideration legislation, geological characteristics and environmental parameters. The GA was used in order to introduce land use changes while maximizing transformation suitability, compactness, economic return, and minimizing soil erosion. The output of the GA was compared to the actual development of the island. The outcomes confirmed the proposed algorithm’s convergence process, while the GA solutions eventually formed a Pareto Front and performed adequately across all objectives. The GA algorithm has proposed reduction of Irrigated farming land by 16%, increase of Dry farming land by 131%, and the maximum allowed by the defined constraints increase of Urban land (100%), mostly on the eastern and central part of Naxos. These changes significantly differ from the actual development of the island. Economic return after optimization increased by 18%, while soil erosion decreased from 1948 t/y to 1843 t/y.展开更多
In order to maintain the overall social interest in land use and improve the level of land administration, an information system for land-use planning and management (ISLUPM) was established, which is composed of pr...In order to maintain the overall social interest in land use and improve the level of land administration, an information system for land-use planning and management (ISLUPM) was established, which is composed of presentation layer, business logic layer and data layer in the general structure. The application support platform of the ISLUPM, built based on COM, COM + and .NET standard components, includes data engine, data management, assemblies, components management, operation management, and interface. Then, an elaboration was made on major functions of the ISLUPM, such as planning revision scheme, planning operation flow, digital processing, thematic analysis and inquiry, and preparation of the chart of reserved land resources. The developed system has been successfully applied to the land-use planning and management work of Longquanyi District, Chengdu, China. It may provide a reference for development of geographic information system (GIS) for land and resources.展开更多
The objective of this study is to weigh and recommend environmentally-optimal regional land-use planning guidelines for coastal regions. The present malaise is assessed, as regards inefficiencies, non-suitability, non...The objective of this study is to weigh and recommend environmentally-optimal regional land-use planning guidelines for coastal regions. The present malaise is assessed, as regards inefficiencies, non-suitability, non-sustainability, enhancing factors of environmental degradation, and potentially destructive consequences of current land-use alteration. Desired situations and goals are considered, and means are proposed for bridging the gap between the present malaise and a desired situation, based on five key approaches developed by the authors. Specific examples of regional approaches are presented. Guidelines and operational measures for sound regional planning the authors have employed in similar circumstances are recommended.展开更多
The objective of this paper is to demonstrate necessity to inform relevant parties about engineering-geological conditions for various practical purposes, especially including appropriate land-use planning. However, t...The objective of this paper is to demonstrate necessity to inform relevant parties about engineering-geological conditions for various practical purposes, especially including appropriate land-use planning. However, the relationship between relevant geological information and the geological environment is vital for foundation engineering purposes, especially where demanding structures are involved. This information is most conveniently structured when accumulated information concerning engineering-geological zones is utilized. This necessarily includes knowledge of rock workability and also of the pre-Quaternary bedrock, and these characteristics were then related to the current built-up area and future development according to the land-use plans in a case study are from the Petrvald Region (Czech Republic). The geological environment of area has been severely influenced by anthropogenic effects of deep black coal mining. Results of this research showed that future development should be founded on spoil banks, dumps, and settling basins. According to the land-use plan, this zone occupies 44.9% of the area of interest, and its materials predominantly emanate from mining in the Ostrava-Karvina Coal District. For future foundation structures planned there, it is imperative to consult detailed engineering-geological study. However, attention to and reliance on this necessity is not reflected in the existing land-use plan.展开更多
In this paper,a detailed data list of water plan is given,based on its characteristics.This paper discusses the principles ofestablishing a system of standards for a water plan database,and amethod of modeling the wat...In this paper,a detailed data list of water plan is given,based on its characteristics.This paper discusses the principles ofestablishing a system of standards for a water plan database,and amethod of modeling the water plan data.The information is presentedin a standardization system graph.展开更多
In this paper, we identify the geographic information systems (GIS), discuss the components of GIS, which integrates five essential components: hardware, software, data, people, and methods. Present the relations betw...In this paper, we identify the geographic information systems (GIS), discuss the components of GIS, which integrates five essential components: hardware, software, data, people, and methods. Present the relations between computer and urban planning, urban planning and GIS. Moreover, the main discussion on a case study that explores the possibility of using ArcView GIS software to assemble, store, manipulate, and analyze historic site- Xinjin ferry district in Zhenjiang.展开更多
Miyun Reservoir is the most important water source to Beijing City. Land-use of the basin plays a great role in the protection of water resources. Hence a sustainable land-use planning is required to optimize land-use...Miyun Reservoir is the most important water source to Beijing City. Land-use of the basin plays a great role in the protection of water resources. Hence a sustainable land-use planning is required to optimize land-use structure and protect water resources in the basin. Based on the complete land-use system analysis in Miyun, a grey multi-objective programming to basin land-use(GMOPBLU) model was developed and applied to land-use planning. Two alternatives were produced and analyzed by means of interactive adjustment and scenario analysis. The results showed the GMOPBLU model is a valuable approach for basin land-use planning.展开更多
Land scarcity has become the prominent obstacle on the way to sustainable development for China. Under the constraints of land shortage, how to allocate the finite land resources to the multiple land users in China co...Land scarcity has become the prominent obstacle on the way to sustainable development for China. Under the constraints of land shortage, how to allocate the finite land resources to the multiple land users in China considering various political, environmental, ecological and economic conditions have become research topics with great significance. In this study, an interval fuzzy national-scale land-use model(IFNLM) was developed for optimizing land systems of China. IFNLM is based on an integration of existing interval linear programming(ILP), and fuzzy flexible programming(FFP) techniques. IFNLM allows uncertainties expressed as discrete interval values and fuzzy sets to be incorporated within a general optimization framework. It can also facilitate national-scale land-use planning under various environmental, ecological, social conditions within a multi-period and multi-option context. Then, IFNLM was applied to a real case study of land-use planning in China. The satisfaction degree of environmental constraints is between 0.69 and 0.97, the system benefit will between 198.25 × 1012 USD and 229.67 × 1012 USD. The results indicated that the hybrid model can help generate desired policies for land-use allocation with a maximized economic benefit and minimized environmental violation risk. Optimized land-use allocation patterns can be generated from the proposed IFNLM.展开更多
To solve the problems caused by irrational land-use, studying the functions of land-use, its changing characteristics, and the relationship between each land-use function will be beneficial for achieving sustainable l...To solve the problems caused by irrational land-use, studying the functions of land-use, its changing characteristics, and the relationship between each land-use function will be beneficial for achieving sustainable land development. In this research, we constructed an evaluation framework of multiple land-use functions(LUFs) based on sustainable land-use theory. Specifically,, we classified the multiple LUFs into three types: agricultural production function(APF), living function(LVF), and ecological service function(ESF).We then spatialized the economic and social data, and implemented the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs) model and RUSLE(Revised Universal Soil Loss Equation) model to evaluate each sub-LUF(crop production, aquatic production, woodlands production, livestock production, living space, life quality, water supply, soil conservation, climate regulation, biological conservation) in central China in 2000 and again in 2015. Moreover, by analyzing the changes to LUFs and the relationships between each LUF change, we were able to discern patterns of LUF change in central China. The results show that: (1)42.12% of total territory in the study area increased their APF from 2000 to 2015, while 43.41% of the lands increased their ESF yet only 8.98% of the lands increased their LVF;(2) in Hubei and Hunan, there was more land with an increase of APF than in Anhui or Jiangxi. The APF in Jiangxi exhibited the greatest decline over time period, the LVF increased more in the provincial capital cities than in other regions, and the ESF expanded more in Jiangxi than in the other provinces;and (3) the changes in APF were significantly and positively correlated with changes in LVF. Additionally, changes in ESF were negatively but non-significantly correlated with changes in APF and LVF.展开更多
Land-use change is an important part of global change research(IGBP,1990-1992).But the majority of researches focus on the natural dr iving force of land use change.In thi s paper,the authors studied the rela tionship...Land-use change is an important part of global change research(IGBP,1990-1992).But the majority of researches focus on the natural dr iving force of land use change.In thi s paper,the authors studied the rela tionship be-tween socio-economic driving facto rs and land-use change with time series in Hainan Island.Based on the stud y for the evolution of administrative system and policies in Hainan Island and the comprehensive analysis on the socia l economy da-ta and changes of social policies,th e socio-economic policies,human activities and land use of Hainan can be divided into three periods with different ch aracters:period from1950to 1978ch aracterized by the planning economi c system,peri-od from 1978to 1988characterized by the transfer of economic system and a doption of open policy,new stage fro m 1988to 1998with high growing speed.On th e other hand the authors describe the character of the periods and land-use change process affected by socio-economic factors.This paper provides an important method for evaluating the development and changes of Hainan social economy dur ing the 50years from 1950to 1999and f orecasting the development of Hainan so-cial economy in future.展开更多
The basic procedure of the Italian Civil Protection Department aims at reducing disaster losses by giving prominence to a proactive strategy, focusing on prevision and prevention of hazard events rather than postdisat...The basic procedure of the Italian Civil Protection Department aims at reducing disaster losses by giving prominence to a proactive strategy, focusing on prevision and prevention of hazard events rather than postdisater activities. Italian law commits municipalities to produce Emergency Plans that include risk scenarios as well as all data required for emergency management, such as structures, infrastructures and human resources. However the law in the matter of Civil Protection does not supply information about how to produce and archive necessary data for emergency planning and management. For this reason, we propose a standard methodology to create a geodatabase using GIS software, to collect all data that could be used by municipalities to create Emergency Plans. The resulting geodatabase provides a tool for hazard mitigation planning, allowing not only the identification of areas at risk, but also the structures, infrastructures and resources needed to overcome a crisis, thus improving all strategies of risk reduction and the resilience of the system [1].展开更多
Under the framework of ecological civilisation,the formulation of territorial spatial planning(TSP) and improvement of spatial governance systems are of great practical significance.Since the founding of the People’s...Under the framework of ecological civilisation,the formulation of territorial spatial planning(TSP) and improvement of spatial governance systems are of great practical significance.Since the founding of the People’s Republic of China,land-use planning(LUP) has experienced profound changes,and tremendous research efforts have been made in that field.However,systematic studies on LUP history are scarce.To bridge the existing gap,this study traced back to the emergence of LUP,described its practice stages,and analysed the evolution of its classification system and methods.Further,the three rounds of general LUP practice and the current TSP over the past 40 years of the reform and opening-up have been discussed.The evolution of LUP was found to be closely related to economic development and could be broadly divided into four stages.The development of land-use classification in China has been slow and can be divided into five stages according to the evolution of the land classification system and important historical events.The development of LUP methods can be divided into two stages,before and after 1978.Since the economic reform,China has successively conducted three rounds of general LUP under different institutional and policy backgrounds.Future development should aim to innovate the theories and methods of TSP with Chinese characteristics and promote the study of village planning and the construction of TSP systems to achieve rural revitalisation and ecological civilisation.展开更多
The author investigates the query optimization problem for parallel relational databases. A multi - weighted tree based query optimization method is proposed. The method consists of a multi - weighted tree based paral...The author investigates the query optimization problem for parallel relational databases. A multi - weighted tree based query optimization method is proposed. The method consists of a multi - weighted tree based parallel query plan model, a cost model for parallel qury plans and a query optimizer. The parallel query plan model is the first one to model all basic relational operations, all three types of parallelism of query execution, processor and memory allocation to operations, memory allocation to the buffers between operations in pipelines and data redistribution among processors. The cost model takes the waiting time of the operations in pipelining execution into consideration and is computable in a bottom - up fashion. The query optimizer addresses the query optimization problem in the context of Select - Project - Join queries that are widely used in commercial DBMSs. Several heuristics determining the processor allocation to operations are derived and used in the query optimizer. The query optimizer is aware of memory resources in order to generate good - quality plans. It includes the heuristics for determining the memory allocation to operations and buffers between operations in pipelines so that the memory resourse is fully exploit. In addition, multiple algorithms for implementing join operations are consided in the query optimizer. The query optimizer can make an optimal choice of join algorithm for each join operation in a query. The proposed query optimization method has been used in a prototype parallel database management system designed and implemented by the author.展开更多
基金funded by Start-Up Funds for Scientific Research of Shenzhen University,Grant No.000002112313.
文摘With the development of the digital city,data and data analysis have become more and more important.The database is the foundation of data analysis.In this paper,the software system of the urban land planning database of Shanghai in China is developed based on MySQL.The conceptual model of the urban land planning database is proposed,and the entities,attributes and connections of this model are discussed.Then the E-R conceptual model is transformed into a logical structure,which is supported by the relational databasemanagement system(DBMS).Based on the conceptual and logical structures,by using Spring Boot as the back-end framework and using MySQL and Java API as the development tools,a platformwith datamanagement,information sharing,map assistance and other functions is established.The functionalmodules in this platformare designed.The results of J Meter test show that the DBMS can add,store and retrieve information data stably,and it has the advantages of fast response and low error rate.The software system of the urban land planning database developed in this paper can improve the efficiency of storing and managing land data,eliminating redundant data and sharing data.
基金Under the auspices of National Natural Science Foundation of China(No.40801069)Special Research Program for Public-welfare Forestry of China(No.200804001)
文摘This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River water- shed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) technology. Then, using the famous land-use change model of Conversion of Land Use and its Effects at Small re- gional extent (CLUE-S), this paper simulated the land use changes under historical trend (HT), urban planning (UP) and ecological protection (EP) scenarios considering urban planning and ecological protection over the next 20 years. The simulated results under UP scenario in 2020 were compared with the planning map to assess the feasibility of us- ing land-use change model to guide regional planning. Results show that forest land, dry farmland, paddy, and shrub land were the main land-use categories. Paddy and dry farmland being converted to urban area and rural settlement characterized the land-use change from 1988 to 2004. The main land-use categories changed over time. Landscape-pattem fragmentation will be worse under HT and UP scenarios, but better in EP scenario. The comparing results of simulated map with planning map in 2020 show that land-use change model is powerful tool to guide regional planning. Land-use scenarios can support regional planning and policy-making through analyzing future consequences scientifically.
文摘The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.
文摘This paper explores the potential application of a modified version of the Non-dominated Sorting Genetic Algorithm (NSGA)-II for land-use planning in Mediterranean islands that constitute a geographical entity with similar characteristics. Study area is the island of Naxos, which is a typical Mediterranean island. In order to monitor the land-use changes of the island for the period 1987-2010, object-based classification of three Landsat images has been carried out. The 1987 land-use classification defined the initial population for the Genetic Algorithm (GA) and the aim was to provide the optimal development scenario for Naxos island taking into consideration legislation, geological characteristics and environmental parameters. The GA was used in order to introduce land use changes while maximizing transformation suitability, compactness, economic return, and minimizing soil erosion. The output of the GA was compared to the actual development of the island. The outcomes confirmed the proposed algorithm’s convergence process, while the GA solutions eventually formed a Pareto Front and performed adequately across all objectives. The GA algorithm has proposed reduction of Irrigated farming land by 16%, increase of Dry farming land by 131%, and the maximum allowed by the defined constraints increase of Urban land (100%), mostly on the eastern and central part of Naxos. These changes significantly differ from the actual development of the island. Economic return after optimization increased by 18%, while soil erosion decreased from 1948 t/y to 1843 t/y.
文摘In order to maintain the overall social interest in land use and improve the level of land administration, an information system for land-use planning and management (ISLUPM) was established, which is composed of presentation layer, business logic layer and data layer in the general structure. The application support platform of the ISLUPM, built based on COM, COM + and .NET standard components, includes data engine, data management, assemblies, components management, operation management, and interface. Then, an elaboration was made on major functions of the ISLUPM, such as planning revision scheme, planning operation flow, digital processing, thematic analysis and inquiry, and preparation of the chart of reserved land resources. The developed system has been successfully applied to the land-use planning and management work of Longquanyi District, Chengdu, China. It may provide a reference for development of geographic information system (GIS) for land and resources.
文摘The objective of this study is to weigh and recommend environmentally-optimal regional land-use planning guidelines for coastal regions. The present malaise is assessed, as regards inefficiencies, non-suitability, non-sustainability, enhancing factors of environmental degradation, and potentially destructive consequences of current land-use alteration. Desired situations and goals are considered, and means are proposed for bridging the gap between the present malaise and a desired situation, based on five key approaches developed by the authors. Specific examples of regional approaches are presented. Guidelines and operational measures for sound regional planning the authors have employed in similar circumstances are recommended.
基金Czech Science Foundation for their support of project(GACR-105/09/1631)
文摘The objective of this paper is to demonstrate necessity to inform relevant parties about engineering-geological conditions for various practical purposes, especially including appropriate land-use planning. However, the relationship between relevant geological information and the geological environment is vital for foundation engineering purposes, especially where demanding structures are involved. This information is most conveniently structured when accumulated information concerning engineering-geological zones is utilized. This necessarily includes knowledge of rock workability and also of the pre-Quaternary bedrock, and these characteristics were then related to the current built-up area and future development according to the land-use plans in a case study are from the Petrvald Region (Czech Republic). The geological environment of area has been severely influenced by anthropogenic effects of deep black coal mining. Results of this research showed that future development should be founded on spoil banks, dumps, and settling basins. According to the land-use plan, this zone occupies 44.9% of the area of interest, and its materials predominantly emanate from mining in the Ostrava-Karvina Coal District. For future foundation structures planned there, it is imperative to consult detailed engineering-geological study. However, attention to and reliance on this necessity is not reflected in the existing land-use plan.
文摘In this paper,a detailed data list of water plan is given,based on its characteristics.This paper discusses the principles ofestablishing a system of standards for a water plan database,and amethod of modeling the water plan data.The information is presentedin a standardization system graph.
文摘In this paper, we identify the geographic information systems (GIS), discuss the components of GIS, which integrates five essential components: hardware, software, data, people, and methods. Present the relations between computer and urban planning, urban planning and GIS. Moreover, the main discussion on a case study that explores the possibility of using ArcView GIS software to assemble, store, manipulate, and analyze historic site- Xinjin ferry district in Zhenjiang.
文摘Miyun Reservoir is the most important water source to Beijing City. Land-use of the basin plays a great role in the protection of water resources. Hence a sustainable land-use planning is required to optimize land-use structure and protect water resources in the basin. Based on the complete land-use system analysis in Miyun, a grey multi-objective programming to basin land-use(GMOPBLU) model was developed and applied to land-use planning. Two alternatives were produced and analyzed by means of interactive adjustment and scenario analysis. The results showed the GMOPBLU model is a valuable approach for basin land-use planning.
基金Under the auspices of National Natural Science Foundation of China(No.41201164)Humanities and Social Science Research Planning Fund,Ministry of Education of China(No.12YJCZH299)
文摘Land scarcity has become the prominent obstacle on the way to sustainable development for China. Under the constraints of land shortage, how to allocate the finite land resources to the multiple land users in China considering various political, environmental, ecological and economic conditions have become research topics with great significance. In this study, an interval fuzzy national-scale land-use model(IFNLM) was developed for optimizing land systems of China. IFNLM is based on an integration of existing interval linear programming(ILP), and fuzzy flexible programming(FFP) techniques. IFNLM allows uncertainties expressed as discrete interval values and fuzzy sets to be incorporated within a general optimization framework. It can also facilitate national-scale land-use planning under various environmental, ecological, social conditions within a multi-period and multi-option context. Then, IFNLM was applied to a real case study of land-use planning in China. The satisfaction degree of environmental constraints is between 0.69 and 0.97, the system benefit will between 198.25 × 1012 USD and 229.67 × 1012 USD. The results indicated that the hybrid model can help generate desired policies for land-use allocation with a maximized economic benefit and minimized environmental violation risk. Optimized land-use allocation patterns can be generated from the proposed IFNLM.
基金Under the auspices of National Natural Science Foundation of China(No.41271534)China Scholarship Council(No.201906770044)。
文摘To solve the problems caused by irrational land-use, studying the functions of land-use, its changing characteristics, and the relationship between each land-use function will be beneficial for achieving sustainable land development. In this research, we constructed an evaluation framework of multiple land-use functions(LUFs) based on sustainable land-use theory. Specifically,, we classified the multiple LUFs into three types: agricultural production function(APF), living function(LVF), and ecological service function(ESF).We then spatialized the economic and social data, and implemented the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs) model and RUSLE(Revised Universal Soil Loss Equation) model to evaluate each sub-LUF(crop production, aquatic production, woodlands production, livestock production, living space, life quality, water supply, soil conservation, climate regulation, biological conservation) in central China in 2000 and again in 2015. Moreover, by analyzing the changes to LUFs and the relationships between each LUF change, we were able to discern patterns of LUF change in central China. The results show that: (1)42.12% of total territory in the study area increased their APF from 2000 to 2015, while 43.41% of the lands increased their ESF yet only 8.98% of the lands increased their LVF;(2) in Hubei and Hunan, there was more land with an increase of APF than in Anhui or Jiangxi. The APF in Jiangxi exhibited the greatest decline over time period, the LVF increased more in the provincial capital cities than in other regions, and the ESF expanded more in Jiangxi than in the other provinces;and (3) the changes in APF were significantly and positively correlated with changes in LVF. Additionally, changes in ESF were negatively but non-significantly correlated with changes in APF and LVF.
文摘Land-use change is an important part of global change research(IGBP,1990-1992).But the majority of researches focus on the natural dr iving force of land use change.In thi s paper,the authors studied the rela tionship be-tween socio-economic driving facto rs and land-use change with time series in Hainan Island.Based on the stud y for the evolution of administrative system and policies in Hainan Island and the comprehensive analysis on the socia l economy da-ta and changes of social policies,th e socio-economic policies,human activities and land use of Hainan can be divided into three periods with different ch aracters:period from1950to 1978ch aracterized by the planning economi c system,peri-od from 1978to 1988characterized by the transfer of economic system and a doption of open policy,new stage fro m 1988to 1998with high growing speed.On th e other hand the authors describe the character of the periods and land-use change process affected by socio-economic factors.This paper provides an important method for evaluating the development and changes of Hainan social economy dur ing the 50years from 1950to 1999and f orecasting the development of Hainan so-cial economy in future.
文摘The basic procedure of the Italian Civil Protection Department aims at reducing disaster losses by giving prominence to a proactive strategy, focusing on prevision and prevention of hazard events rather than postdisater activities. Italian law commits municipalities to produce Emergency Plans that include risk scenarios as well as all data required for emergency management, such as structures, infrastructures and human resources. However the law in the matter of Civil Protection does not supply information about how to produce and archive necessary data for emergency planning and management. For this reason, we propose a standard methodology to create a geodatabase using GIS software, to collect all data that could be used by municipalities to create Emergency Plans. The resulting geodatabase provides a tool for hazard mitigation planning, allowing not only the identification of areas at risk, but also the structures, infrastructures and resources needed to overcome a crisis, thus improving all strategies of risk reduction and the resilience of the system [1].
基金National Natural Science Foundation of China,No.42001187。
文摘Under the framework of ecological civilisation,the formulation of territorial spatial planning(TSP) and improvement of spatial governance systems are of great practical significance.Since the founding of the People’s Republic of China,land-use planning(LUP) has experienced profound changes,and tremendous research efforts have been made in that field.However,systematic studies on LUP history are scarce.To bridge the existing gap,this study traced back to the emergence of LUP,described its practice stages,and analysed the evolution of its classification system and methods.Further,the three rounds of general LUP practice and the current TSP over the past 40 years of the reform and opening-up have been discussed.The evolution of LUP was found to be closely related to economic development and could be broadly divided into four stages.The development of land-use classification in China has been slow and can be divided into five stages according to the evolution of the land classification system and important historical events.The development of LUP methods can be divided into two stages,before and after 1978.Since the economic reform,China has successively conducted three rounds of general LUP under different institutional and policy backgrounds.Future development should aim to innovate the theories and methods of TSP with Chinese characteristics and promote the study of village planning and the construction of TSP systems to achieve rural revitalisation and ecological civilisation.
基金Supported by the National Natural Science Foundation of China National (9846-004) '863' High -Technique Program of China (8
文摘The author investigates the query optimization problem for parallel relational databases. A multi - weighted tree based query optimization method is proposed. The method consists of a multi - weighted tree based parallel query plan model, a cost model for parallel qury plans and a query optimizer. The parallel query plan model is the first one to model all basic relational operations, all three types of parallelism of query execution, processor and memory allocation to operations, memory allocation to the buffers between operations in pipelines and data redistribution among processors. The cost model takes the waiting time of the operations in pipelining execution into consideration and is computable in a bottom - up fashion. The query optimizer addresses the query optimization problem in the context of Select - Project - Join queries that are widely used in commercial DBMSs. Several heuristics determining the processor allocation to operations are derived and used in the query optimizer. The query optimizer is aware of memory resources in order to generate good - quality plans. It includes the heuristics for determining the memory allocation to operations and buffers between operations in pipelines so that the memory resourse is fully exploit. In addition, multiple algorithms for implementing join operations are consided in the query optimizer. The query optimizer can make an optimal choice of join algorithm for each join operation in a query. The proposed query optimization method has been used in a prototype parallel database management system designed and implemented by the author.